Comment 1 for bug 1255420

That configuration file can be found in neutron-plugin-mlnx-agent:

dpkg -c neutron-plugin-mlnx-agent_1%3a2013.2-0ubuntu1_all.deb
drwxr-xr-x root/root 0 2013-10-17 17:13 ./
drwxr-xr-x root/root 0 2013-10-17 17:13 ./etc/
drwxr-xr-x root/root 0 2013-10-17 17:13 ./etc/neutron/
drwxr-xr-x root/root 0 2013-10-17 17:13 ./etc/neutron/plugins/
drwxr-xr-x root/root 0 2013-10-17 17:13 ./etc/neutron/plugins/mlnx/
-rw-r--r-- root/root 1816 2013-10-17 15:01 ./etc/neutron/plugins/mlnx/mlnx_conf.ini
drwxr-xr-x root/root 0 2013-10-17 17:13 ./etc/init/
-rw-r--r-- root/root 517 2013-10-17 15:55 ./etc/init/neutron-plugin-mlnx-agent.conf
drwxr-xr-x root/root 0 2013-10-17 17:13 ./usr/
drwxr-xr-x root/root 0 2013-10-17 17:13 ./usr/share/
drwxr-xr-x root/root 0 2013-10-17 17:13 ./usr/share/doc/
drwxr-xr-x root/root 0 2013-10-17 17:14 ./usr/share/doc/neutron-plugin-mlnx-agent/
-rw-r--r-- root/root 1418 2013-10-17 15:55 ./usr/share/doc/neutron-plugin-mlnx-agent/copyright
drwxr-xr-x root/root 0 2013-10-17 17:13 ./usr/bin/
-rwxr-xr-x root/root 187 2013-10-17 17:13 ./usr/bin/neutron-mlnx-agent
lrwxrwxrwx root/root 0 2013-10-17 17:14 ./usr/share/doc/neutron-plugin-mlnx-agent/NEWS.Debian.gz -> ../python-neutron/NEWS.Debian.gz
lrwxrwxrwx root/root 0 2013-10-17 17:14 ./usr/share/doc/neutron-plugin-mlnx-agent/changelog.Debian.gz -> ../python-neutron/changelog.Debian.gz

Is there a neutron-server side aspect to this plugin as well? its not one we test or use in OpenStack CI for Ubuntu.